Based on the preface, what is the role and value of a detailed, poetic Guru biography within the devotional tradition of Maharashtra?

The preface elevates the role of a detailed, poetic Guru biography to a central place in the devotional tradition of Maharashtra. It is presented not merely as a historical record but as a powerful tool for spiritual service and advancement. As outlined in Chapter 0, such a work facilitates a specific form of devotional practice called a Parayan or Saptah, which less comprehensive collections cannot support for a single saint. By providing a "comprehensive, and famous" work, like the Guru Charitra or the Shri Sai Satcharita, it allows devotees to immerse themselves in the Guru's life. This act serves a dual purpose: it is a service to the Guru by the author, and it allows countless other devotees to "achieve the purpose of their lives" through study.